US8713973B2 - Glass tempering method and apparatus - Google Patents

Glass tempering method and apparatus Download PDF

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Publication number
US8713973B2
US8713973B2 US13/261,066 US201013261066A US8713973B2 US 8713973 B2 US8713973 B2 US 8713973B2 US 201013261066 A US201013261066 A US 201013261066A US 8713973 B2 US8713973 B2 US 8713973B2
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United States
Prior art keywords
distance
nozzles
glass
glass sheet
tempering
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Expired - Fee Related, expires
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US13/261,066
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US20120073327A1 (en
Inventor
Robert J. Boisselle
John Tomik
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Pilkington Group Ltd
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Pilkington Group Ltd
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    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B27/00—Tempering or quenching glass products
    • C03B27/04—Tempering or quenching glass products using gas
    • C03B27/0404—Nozzles, blow heads, blowing units or their arrangements, specially adapted for flat or bent glass sheets
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B27/00—Tempering or quenching glass products
    • C03B27/04—Tempering or quenching glass products using gas
    • C03B27/0413—Stresses, e.g. patterns, values or formulae for flat or bent glass sheets
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B27/00—Tempering or quenching glass products
    • C03B27/04—Tempering or quenching glass products using gas
    • C03B27/0417—Controlling or regulating for flat or bent glass sheets
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B27/00—Tempering or quenching glass products
    • C03B27/04—Tempering or quenching glass products using gas
    • C03B27/044—Tempering or quenching glass products using gas for flat or bent glass sheets being in a horizontal position
    • C03B27/0442—Tempering or quenching glass products using gas for flat or bent glass sheets being in a horizontal position for bent glass sheets
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B27/00—Tempering or quenching glass products
    • C03B27/04—Tempering or quenching glass products using gas
    • C03B27/044—Tempering or quenching glass products using gas for flat or bent glass sheets being in a horizontal position
    • C03B27/0442—Tempering or quenching glass products using gas for flat or bent glass sheets being in a horizontal position for bent glass sheets
    • C03B27/0445—Tempering or quenching glass products using gas for flat or bent glass sheets being in a horizontal position for bent glass sheets the quench unit being adapted to the bend of the sheet

Definitions

  • the present invention relates to an improved apparatus for tempering glass sheets and a method of tempering utilizing that apparatus.
  • glass tempering or heat treatment is the subject of many patents, for example:
  • U.S. Pat. No. 4,314,836 describes a construction and arrangement of a tempering medium supply system that is said to provide relatively wide escape paths in the direction of the glass sheet thickness for blasts of tempering medium applied toward the central portion of the glass sheet compared to the escape paths provided in said direction for blasts of tempering medium applied to the portion of the glass sheet beyond the central portion.
  • the resulting tempered glass sheets utilizing the process of the present invention are said to produce fragments meeting code requirements in the central portion as well as the portion beyond the central portion when subjected to destructive testing.
  • U.S. Pat. No. 4,323,385 describes a process for uniformily tempering the entirety of a glass sheet utilizing plenum chambers having aperture walls facing the opposite major surfaces of the glass sheet, wherein the apertures are constructed and arranged to be smaller and more closely spaced in the portion of the plenum that faces the central portion of the glass sheet during tempering than the apertures provided in the wall outside the central portion.
  • Nozzles extending from said apertures are constructed and arranged so that nozzles extending from the relatively small diameter, more closely spaced apertures of the central portion of the wall are longer, and narrower and have their ends closer to the major surface of the glass sheet than the relatively widely spaced nozzles of relatively larger cross-section that extend from the remaining apertures in the aperture wall.
  • U.S. Pat. No. 4,508,783 describes a method of differentiated rate of hardening of a glass sheet by blowing a cooling gas in the direction of the sheet having two zones, from nozzles. According to the invention, a simultaneous solidification of the glass sheet is said to be produced at both zones of the sheet in spite of the differentiated treatments applied to establish a difference of hardening between the different zones of the sheet.
  • U.S. Pat. No. 4,773,926 describes a tempering process for glass sheets of ⁇ 2mm in thickness in which process, a plurality of nozzles from which a gas flow emanates, are located so that their free ends are directed toward the glass sheet in a position spaced slightly apart from the glass surface.
  • Each nozzle is pierced by a narrow, calibrated orifice and the feed pressure of each nozzle is maintained for purposes of blowing the gas, generally air, at least at sonic speed toward the surface of the sheet.
  • the configuration of the nozzles are said to ensure that the speed of the blowing gas is, at least, at sonic speed at the surface of the glass sheet, thus optimizing coating power.
  • One measure to increase the evacuation of the blown air is said to be accomplished by the use of nozzles having longer tubular bodies extending toward the free end.
  • the nozzles may be longer in relation to the width of the tempering station. Additionally, or alternatively, the flow of blown air may be increased in volume per unit surface area.
  • U.S. Pat. No. 6,412,309 describes a glass quenching apparatus including a first nozzle group for jetting blower air onto opposite surfaces of the glass sheet, the first nozzle group being stationary nozzles, and a second nozzle group being movable nozzles for jetting compressor air onto at least one of the opposite surfaces of the glass sheet, which nozzles are capable of moving parallel to a plane of the glass sheet.
  • the movable nozzle group can be located, it is said, at an optimum position with respect to, for example, a hard-to-cool portion of a glass sheet.
  • the present invention relates to a glass tempering apparatus comprised of at least one and preferably of two glass tempering modules, at least one such glass tempering module being capable of selectively delivering specified volumes of a tempering medium at increased velocity to designated areas of a moving glass sheet to create desired stress differentials in such designated areas, by the selective arrangement and utilization of quench nozzles at different distances from the surface of the glass sheet to be tempered.
  • nozzles arranged in rows parallel to the direction of travel of the glass sheet, spanning a specified distance on either side of the centerline of the glass tempering apparatus, certain selected nozzles being at a reduced distance from the surface of the glass sheet to be tempered delivering tempering medium at an increased velocity, have been found to substantially reduce the incidence of inadequate tempering of, in particular, large sheets of glass.
  • a method of improved tempering utilizing the apparatus of the present invention is also provided.
  • FIG. 1 is a plan view of a glass tempering line in accordance with the invention.
  • FIG. 2 is a plan view of a representative glass sheet showing areas prone to insufficient tempering.
  • FIG. 3 is a perspective view of a conventional blasthead assembly.
  • FIG. 4 is a perspective view of a blasthead assembly with variable length nozzles in accordance with the invention.
  • FIG. 5 is a cross-sectional view of first and second complementary tempering assemblies in accordance with the invention.
  • FIG. 6 is a graph/chart of quench air delivered to glass across the width of the blasthead assembly in accordance with a preferred embodiment of the invention.
  • FIG. 7 is a graph/chart comparing the occurrence of splines in a glass sheet utilizing the tempering technology of the present invention, to a conventional tempering apparatus.
  • FIG. 8 is a graph/chart comparing the minimum glass particle count which occurs on selective breakage testing of a glass sheet utilizing the tempering technology of the present invention, to a conventional tempering apparatus.
  • the present invention relates to a glass tempering apparatus 10 and to a method of tempering glass sheets utilizing such apparatus. More specifically, the invention relates to an apparatus 10 for, and method of selectively delivering desired volumes of tempering medium at increased velocity to one or more areas of at least one major surface of a glass sheet 12 .
  • the glass sheet 12 is, for example, adapted for use as a vehicle window.
  • the apparatus 10 of the present invention allows for significant improvement in tempering of large glass sheets 10 , such as vehicle backlights, by directing specified volumes of tempering medium, at increased velocity, toward specified areas of the glass sheet 10 where glass quality testing has shown that tempering may have been insufficient.
  • tempering break patterns i.e., break patterns of elongated glass shards known as “splines”, rather than small, rounded particles, occurs a relatively consistent distance (distance “A”) transversely from, and on either side of, the centerline of the glass tempering apparatus.
  • distance “A” The width of the area in which the splines typically occur tends also to be relatively consistent, and is sometimes referred to herein as distance “B”.
  • Tempering apparatus such as the present invention are sometimes referred to as “blastheads”, “quench modules” or “quench boxes.”
  • the tempering apparatus 10 can be used as a component of a typical glass tempering line 14 , shown schematically in FIG. 1 .
  • a conventional blasthead assembly is shown in FIG. 3 .
  • the quench nozzles are configured to follow the contour of the shaped glass sheet.
  • the distal ends of the quench nozzles remain substantially a uniform distance from the surface of the shaped glass sheet.
  • a tempering apparatus 10 in accordance with the present invention is shown in FIG. 4 .
  • tempering medium preferably air
  • the glass sheet 12 In the direction of travel of the glass sheet 12 , in accordance with the invention, the glass sheet 12 first encounters a first zone having a first plurality of nozzles 16 , preferably arranged in staggered rows, sometimes known as a “domino five” pattern, although other nozzle patterns are within the scope of the invention.
  • the moving glass sheet 12 then encounters a second zone having a second plurality of nozzles 18 arranged in parallel rows, sometimes known as a “striper” or a modified striper.
  • the length of the nozzles varies in an area on either side transversely of the centerline of the apparatus. Distances “A”, “B” and “C” as designated on the glass sheet 12 of FIG.
  • the glass sheet 12 encounters a third zone having a third plurality of nozzles 20 in staggered rows, such as the domino five, or modified domino five pattern.
  • the length of the nozzles in the first, second and third pluralities of nozzles 16 , 18 , 20 are predetermined to substantially conform to the shape of the glass sheet 12 to be tempered.
  • the modified striper in the modified striper portion 18 of the tempering apparatus 10 , and in a direction transverse to the direction of glass travel, the modified striper, according to the present invention, can be described as parallel rows of nozzles from which cooling air typically at a temperature of from 50° F. to 150° F. is emitted toward the glass sheet 10 .
  • the distance of the end of the nozzles From the surface of the glass sheet in the parallel rows transverse distance “A” on either side of the centerline of the glass tempering apparatus 10 ′ can be designated as x, and is preferably on the order of 80-90 mm.
  • These nozzles are typically about 6-12 mm, preferably about 6-9 mm, in diameter.
  • the distance of the end of the second plurality of nozzles 18 from the glass can be expressed as y, where y is less than x.
  • the nozzle distance from the glass surface is on the order of 60-70 mm.
  • the diameter of the nozzles is typically about 6-12 mm, preferably about 6-9 mm.
  • the velocity of tempering medium that can be delivered to a selected area of the surface of the glass sheet is substantially increased, preferably to on the order of 15% or more over the velocity delivered by conventional striper modules.
  • a graphical representation of the variation in the velocity of tempering medium delivered in the modified striper module is shown in FIG. 6 .
  • the temperature of the tempering medium generally is from 50° F. to 150° F.
  • the heat transfer, away from the glass surface in the transverse distance “B” where the nozzles are y distance from the glass surface is on the order of 10% or more greater than in areas where the nozzle distance from the glass surface is x.
  • transverse distance “C” the distance of the end of the nozzles from the substrate surface is x, i.e. on the order of 80-90 mm. These nozzles are typically about 6-12 mm, preferably 6-9 mm, in diameter. In accordance with the invention, in a direction transverse to either side of the centerline of the glass tempering assembly, transverse distances A, B, and C will be dependent on the size and geometry of the glass sheet 12 to be tempered.
  • V f V o ⁇ K ⁇ ⁇ D o D T ⁇ ⁇
  • Quench module pressure was between 54′′ and 47′′ of water column.
  • Glass heating furnace temperature was 652° C.-657° C.
  • One way of determining the effectiveness of a glass tempering process is by comparison with certain regulatory standards for minimum particle count and maximum spline length when the tempered glass is fractured. For purposes of this application, tempering is deemed to be satisfactory if minimum particle count is greater than 40 particles per 50 mm 2 , while no spline is more than 75 mm in length.
  • spline is meant a generally elongate glass shard which remains essentially intact after the glass is fractured.
  • Table 1 shows results of fracturing five glass samples tempered utilizing a set of conventional quench modules, that is upper and lower quench modules, having alternating areas of nozzles in domino five and striper patterns, the nozzles conforming to the shape of the glass being tempered. No selectively extended length nozzles were present in either the upper or lower quench nozzles.
  • Tables 2 and 3 show results of fracturing of a number of glass samples tempered utilizing a set of quench modules having extended length nozzles in selected areas of both upper and lower quench nozzles. Additional heating (differential heating) of the area of the glass substrate affected by the extended quench nozzles was tested in, Examples 6-11. No such differential heating was utilized for Examples 12-21. Differential heating in the areas affected by the extended nozzles appears to somewhat increase the minimum particle counts observed, but did not significantly affect spline length. Minimum particle counts are well above the minimum number of 40/50 mm 2 . Likewise, maximum spline length for Examples 6-21 is well below 75 mm.
  • Table 4 shows results of fracturing of a number of glass samples tempered utilizing a set of quench modules having extended nozzles in selected areas of the upper quench module only, according to the invention.
  • Minimum particle counts and maximum spline lengths are as good as, or better than, those where extended nozzles were utilized in both upper and lower quench modules as in Examples 6-21.
  • extended nozzles in both upper and lower quench nozzles are not necessary to achieve good tempering in areas of large glass sheets where obtaining such results has been difficult with conventional quench modules.
  • a second tempering apparatus 22 having all nozzles approximately the same distance from the surface of the substrate and a shape substantially conforming to the shape of the glass sheet to be tempered, and complementary to the first glass tempering apparatus is spaced opposite and apart from the first tempering apparatus 10 a distance sufficient for the glass sheet 12 to be tempered to pass therebetween, the second glass tempering apparatus 22 being capable of directing desired volumes of tempering medium at a predetermined velocity toward the second surface of the glass sheet.

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  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Mathematical Physics (AREA)
  • Re-Forming, After-Treatment, Cutting And Transporting Of Glass Products (AREA)
US13/261,066 2009-06-15 2010-06-08 Glass tempering method and apparatus Expired - Fee Related US8713973B2 (en)

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Application Number Priority Date Filing Date Title
US13/261,066 US8713973B2 (en) 2009-06-15 2010-06-08 Glass tempering method and apparatus

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US18691809P 2009-06-15 2009-06-15
US13/261,066 US8713973B2 (en) 2009-06-15 2010-06-08 Glass tempering method and apparatus
PCT/US2010/001645 WO2010147624A1 (en) 2009-06-15 2010-06-08 Improved glass tempering method and apparatus

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US8713973B2 true US8713973B2 (en) 2014-05-06

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US (1) US8713973B2 (pl)
EP (1) EP2443071B1 (pl)
JP (1) JP5670446B2 (pl)
CN (1) CN102459105B (pl)
BR (1) BRPI1012061B1 (pl)
ES (1) ES2421267T3 (pl)
PL (1) PL2443071T3 (pl)
WO (1) WO2010147624A1 (pl)

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Publication number Priority date Publication date Assignee Title
EP3408234A4 (en) * 2016-01-31 2019-10-23 Corning Incorporated THERMALLY REINFORCED GLASS SHEETS HAVING REDUCED REFRACTIVE INDEX OR BIRRAFRINGENCE INDEX
EP3408244A1 (en) * 2016-01-31 2018-12-05 Corning Incorporated Thermally strengthened glass sheets having characteristic near-edge retardance
EP3246295B1 (en) * 2016-05-17 2021-07-07 Glaston Finland Oy Method for tempering glass sheets

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1157391A (en) 1965-09-09 1969-07-09 Saint Gobain Improvements in or relating to Vehicle Windscreens
US4314836A (en) 1980-08-04 1982-02-09 Ppg Industries, Inc. Glass sheet tempering apparatus with nozzle arrangement providing fluid escape paths and method of tempering glass sheets
US4323385A (en) 1980-07-21 1982-04-06 Ppg Industries, Inc. Nozzle arrangement for glass sheet tempering apparatus
US4343645A (en) 1977-02-07 1982-08-10 Asahi Glass Company, Ltd. Quenching apparatus for tempering curved glass plates
US4508783A (en) 1982-04-16 1985-04-02 Saint-Gobain Vitrage Method for the differentiated hardening of glass sheets, especially of automobile windshields, and tempered glass sheet
US4773926A (en) 1983-06-14 1988-09-27 Saint-Gobain Vitrage Tempering of glass
US6412309B1 (en) 1999-07-13 2002-07-02 Nippon Sheet Glass Co., Ltd. Glass quenching apparatus
WO2003101898A1 (en) * 2002-05-30 2003-12-11 Feracitas Oy Method for cooling the glass sheet
US20060121281A1 (en) 2002-09-04 2006-06-08 Central Glass Company, Limited Thermally tempered glass, and method and apparatus for manufacturing the glass
US20070122580A1 (en) * 2005-11-29 2007-05-31 Krall William R Jr Apparatus and method for tempering glass sheets
US20090173106A1 (en) * 2008-01-04 2009-07-09 Boisselle Robert J Glass tempering method and apparatus

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5460316A (en) * 1977-10-22 1979-05-15 Central Glass Co Ltd Apparatus for heattbend strengthening treatment of glass plate
US4402723A (en) * 1982-01-28 1983-09-06 Ppg Industries, Inc. Nozzle arrangement for pass-through glass sheet tempering apparatus
US6412390B1 (en) 1999-08-20 2002-07-02 Frank J. Dindl Low impulse firing adapter for combination gas and recoil operated weapons

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1157391A (en) 1965-09-09 1969-07-09 Saint Gobain Improvements in or relating to Vehicle Windscreens
US4343645A (en) 1977-02-07 1982-08-10 Asahi Glass Company, Ltd. Quenching apparatus for tempering curved glass plates
US4323385A (en) 1980-07-21 1982-04-06 Ppg Industries, Inc. Nozzle arrangement for glass sheet tempering apparatus
US4314836A (en) 1980-08-04 1982-02-09 Ppg Industries, Inc. Glass sheet tempering apparatus with nozzle arrangement providing fluid escape paths and method of tempering glass sheets
US4508783A (en) 1982-04-16 1985-04-02 Saint-Gobain Vitrage Method for the differentiated hardening of glass sheets, especially of automobile windshields, and tempered glass sheet
US4773926A (en) 1983-06-14 1988-09-27 Saint-Gobain Vitrage Tempering of glass
US6412309B1 (en) 1999-07-13 2002-07-02 Nippon Sheet Glass Co., Ltd. Glass quenching apparatus
WO2003101898A1 (en) * 2002-05-30 2003-12-11 Feracitas Oy Method for cooling the glass sheet
US20060121281A1 (en) 2002-09-04 2006-06-08 Central Glass Company, Limited Thermally tempered glass, and method and apparatus for manufacturing the glass
US20070122580A1 (en) * 2005-11-29 2007-05-31 Krall William R Jr Apparatus and method for tempering glass sheets
US20090173106A1 (en) * 2008-01-04 2009-07-09 Boisselle Robert J Glass tempering method and apparatus

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Publication number Publication date
BRPI1012061B1 (pt) 2020-01-21
WO2010147624A1 (en) 2010-12-23
PL2443071T3 (pl) 2013-09-30
EP2443071A1 (en) 2012-04-25
JP5670446B2 (ja) 2015-02-18
ES2421267T3 (es) 2013-08-30
US20120073327A1 (en) 2012-03-29
CN102459105B (zh) 2015-02-04
BRPI1012061A2 (pt) 2018-06-19
JP2012530029A (ja) 2012-11-29
EP2443071B1 (en) 2013-05-01
CN102459105A (zh) 2012-05-16

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